6th March 2024

Torsade de pointes

This is a polymorphic VT which occurs with a prolonged QT interval (measured from start of Q wave to end of T wave). A long QT may be a result of a congenital genetic abnormality or acquired (see Table 3).  Management includes stopping the precipitating agent which may resolve the episode of torsade. IV Magnesium is administered to stabilise the cardiac membrane and where there is haemodynamic instability DCCV is used. 

 Table 3: Causes of QT prolongation. [Adapted from the Oxford Textbook of Medicine].